From the Magazine

Road hazards threaten rover

As the Curiosity rover chugs across the surface of Mars, mission scientists worry that wheel damage could cut the mission short. Curiosity is bound for Mount Sharp, a 5.5-kilometer-high mountain surrounded by water-altered sediments that scientists want to probe for signs of ancient life. But its path takes it across outcrops of a hard, fractured rock formation, and photos show that sharp stones honed by the martian wind are puncturing the rover's thin aluminum wheels. Mission planners hope to minimize the damage by taking detours into sandy valleys and are conducting sandbox simulations on Earth to gauge what lies ahead.